binutils: Heap-based buffer overflow in bfd_getl_signed_32() in libbfd.c because sh_entsize is not validated in _bfd_elf_slurp_secondary_reloc_section() in elf.c

An issue was discovered in the Binary File Descriptor BFD library aka libbfd, as distributed in GNU Binutils 2.35.1. A heap-based buffer over-read can occur in bfdgetlsigned32 in libbfd.c because shentsize is not validated in bfdelfslurpsecondaryrelocsection in elf.c...